Run Your Car on Cornstalks and Grass Clippings?

May 2006
By
PATRICK BEDARD

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Fill 'er up with switch grass? When our "big oil" President tossed this Native American prairie grass into his January State of the Union speech, in the same breath with "wood chips" and "stalks," as a way to make "ethanol practical and competitive within six years," the guy at this keyboard groaned. Couldn't we just run our cars on presidential hot air?

Bush went on to say that this and other technologies would let us replace more than 75 percent of our oil imports from the Middle East by 2025.

Funny how this date for liberating ourselves from foreign oil keeps getting kicked down the road. During the first Arab oil embargo — that was in 1973 — President Richard Nixon announced Project Independence, saying that by 1980 "the United States will not be dependent on any other country for the energy we need."

When Jimmuh Carter took over in 1977, he famously declared energy independence to be "the moral equivalent of war." Cellulosic ethanol from switch grass and other biomass was part of his plan to be free of foreign energy sources by 1990.

In defense of the much-maligned peanut farmer, he was not responsible for the entire 10-year slip from Nixon's original 1980 deadline. Gerald Ford, the White House resident from 1974 to 1977, had previously pushed the date off to 1985. Still, in the years I've been holding down this page, the dawn of American energy self-sufficiency has been punted into the future by 45 years. I'd call that a rare display of good judgment by our government.

We could be self-sufficient now. All it would take would be a willingness to pay nearly a buck extra per gallon for ethanol made from corn. But paying more for each mile we drive — without some other benefit — would just make us poorer.

And let's be clear. There is no benefit. The most optimistic assessment I've seen on ethanol was a study by the University of California, Berkeley, published in January of this year. "Putting ethanol instead of gasoline in your tank...is probably no worse for the environment than burning gasoline," said the authors.

Some folks would get pleasure from denying our dollars to the Arabs, until they get the bill. We do business with the Arabs for one reason — they have the cheapest oil. We don't have to like them. What we like instead is more miles from our dollars.

Ethanol from corn is a "mature industry," according to the U.S. Department of Energy, so price improvements will be few. That means the subsidies necessary to produce it — 51 cents for each gallon now from the feds, and many states add 10 to 40 cents per gallon on top of that — will continue as long as politicians choose to subsidize farmers and others.

This is not to say that running cars on ethanol, the alcohol from fermented vegetable matter, is an entirely bad idea. We already have about five million "flex fuel" cars on the road that can run on gasoline-ethanol mixtures up to 85-percent ethanol (E85). Ethanol packs a large amount of energy into a gallon compared with alternatives such as natural gas, LPG, and hydrogen. It's not as good as gasoline, however; you need about 1.5 gallons of ethanol to drive the same distance as on one gallon of gasoline, according to the DOE. This means poorer mileage, so you'll need a bigger tank for the same range.

Ethanol has other problems, too. To ensure good engine starting, it needs to be mixed with gasoline. And that mixture has higher smog-producing evaporative emissions. Moreover, ethanol can't be shipped in pipelines because it picks up water. Working around these problems raises the cost of an already costly fuel.

Which brings us to Mr. Bush's ethanol from "wood chips, stalks, or switch grass." These are "biomass" sources, a category that includes everything from forest thinnings to municipal garbage. Unlike corn, which is a food, these cellulosic materials have little use and are therefore cheap. Here's the gotcha: Turning them into ethanol costs more than making it from corn.

Still, the siren of technology sings so sweetly. If we could put a man on the moon, we can surely turn grass clippings into fuel. That's the dream, anyway.

Here's the reality. To make ethanol, you need sugars. They can be fermented into alcohol. Fruits have sugars, so the alcohol comes easily. Wine dates back to biblical times.

Grains don't have sugars, but they have starches. Starches can be converted to sugars. Beer and whiskey start with grains.

But you don't hear of switch-grass vodka. It's possible to turn the cellulosic structure of woody plants into a form of sugar, but the proven methods all use sulfuric acid and make expensive messes. Chemists think they see another way. Instead of sulfuric acid, an enzyme not so different from that used to stonewash jeans could be used to convert the cellulose to a form of sugar. Unfortunately, this particular sugar is a reluctant participant in fermentation, but just the right yeast — it has to be genetically engineered — could do the job.

Research is needed here to drive down the costs of the enzymes and yeasts and to raise the ethanol yield. The President says six more years.

Absent from the President's declaration of energy independence was this season's favorite biofuel — used french-fry oil. Wait till the dark of night, then back your diesel up to the barrel behind McDonald's. All the smartest pirates fill up this way, according to the media. I heard it again a few weeks ago, this time on an NPR cooking show.

Actually, this is a surefire recipe for clogged injectors. However, used restaurant "grease," known in the recycling trade as yellow grease, or any vegetable oil, can be transformed into a substitute for diesel fuel by a chemical process known as transesterification. It's a good substitute, too, much closer to diesel than ethanol is to gasoline. Of course, the feds have subsidies going for biodiesel, as much as 90 cents a gallon to producers. And some states have sweetened the pot with tax cuts up to 20 cents a gallon.

The good news: We have lots of fuel possibilities beyond oil. Looking only at the cost of feedstocks, 85 cents will buy enough corn for a gallon of ethanol, $1.08 worth of yellow grease will make a gallon of biodiesel, or you can use $1.63 worth of soybean oil. What you won't see, as you scan down the list of farm commodities, is a price for switch grass. It's not a commercial crop.

So when will we be filling up with switch-grass ethanol? That's easy. Not before farmers plant huge fields of a rangy grass that grows over your head. When you start hearing of switch-grass subsidies, we'll be close.

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